I tried that fly "drill" of UW arm recovery. Initially - kicking as the arms approached the thighs - (think they might have been slowing down as a prelude to pushing forwards again UW) - only my head as far as the goggles came above the surface - so couldn't get an inhalation in. After a couple of "false starts" I got the knack of it - but felt it was a bit of a desperate effort to get the mouth above the water line. That tells me that in addition to the arms not moving with enough "oomph" towards the end of their up-sweep, my major kick downbeat is not all that effective! I did 2 lengths of it and then came to the conclusion I will NOT be adding that drill to my usual routine!